FLOW AND HEAT TRANSFER OVER A POROUSLY COVERED CYLINDER

Abstract

Across various industries and in many instances in daily life, bluff bodies are found in engineering applications. From heat exchangers in process industries to vehicles on roads and aircrafts in the air, bluff bodies are ubiquitous. When a bluff body is present surrounded by a flowing fluid, a phenomenon termed as Wake Formation occurs that can potentially generate large-scale unsteady forces. Not only do these decrease the efficiency of the motion of the bluff body, but also result in energy losses of the fluid. To combat the same and hence enhance the energy efficiency in the system, many researchers have proposed the usage of a porous covering on the solid body. In other circumstances, particularly in industry, such a system is employed for heat transmission. Cross-flow heat exchangers are an excellent example. Because of the flow separation and short contact duration, the heat transfer properties are also poor. The proposed approach of using a porous coating on the bluff body is also expected to facilitate heat transmission. The thermo-hydraulic characteristics of the fluid travelling around a solid object coated with a porous layer are noteworthy. These characteristics are beneficial in the company by boosting the efficiency of equipment such as heat exchangers. They also have several applications in marine engineering, structural engineering, and textile production, to name a few. As porous covers increase the contact surface area, reduce the flow separation and improve the contact time, they increase the overall efficiency relative to the performance of the naked solid. Furthermore, there is a need to determine the parametric behaviour of porous media in transport phenomena to better understand it. Therefore, their thermo-hydraulic applications must be studied.